Project Summary: BloodCenter of Wisconsin (BCW) together with its consortium partner, the University of Wisconsin (UW) were awarded Core Clinical Center (CCC) status when the Transfusion Medicine and Hemostasis (TMH) Clinical Trial Network (CTN) began in 2002. Wisconsin TMH investigators have been active participants in Network activities over the initial 5 years of funding, helping to develop trials in several of the key areas being addressed by the Network and enrolling patients in the first approved Network study - Determination of the Optimal Prophylactic Platelet Dose Strategy to Prevent Bleeding in Thrombocytopenic Patients or PLADO. This proposal is to continue our CCC's participation in the TMH-CTN over the next 5 years, helping to build on and implement additional clinical trials in these areas of medicine. Specifically, we propose to: 1) Continue our participation in the TMH-CTN trials that have been activated so far (PLADO, Study of Hemostasis and Invasive Procedures (SHIP), and Rituximab for the treatment of Inhibitors in Congenital Hemophilia A (RICH)) and to add to these, new trials as they are approved (e.g. Pipeline trials: HIT Observational Thromboembolism Study (HOT), Study of TTP and Rituximab: A Randomized Clinical Trial (STAR) and High Dose Granulocyte Transfusions for the Treatment of Infections in Neutropenia (the Granulocyte Trial)) and others as they are developed and approved. 2) Participate actively in the Network Steering Committee and Sub-Committee activities in proposing, developing and bringing to Network approval, additional relevant studies in the areas of hemostasis and transfusion medicine 3) Develop collaborative relationships and support training opportunities to facilitate the success of the proposed clinical trials and further the fields of transfusion medicine and hemostasis. 4) Together with TMH Colleagues, disseminate results of the TMH CTN through presentation and publication of clinical trial results and other TMH-CTN activities. Relevance: We believe that the trials developed to date all address important questions in transfusion medicine and hemostasis that required Network participation to be successful. This is in keeping with both the original RFA proposal and the stated objectives of the RFA for continuation of the TMH-CTN.